I have filed a bug report asking for Qgis to give a warning... ----- Regards Morten Qgis 1.8.0 Stand alone installer in Win7 64 bit -- View this message in context: http://osgeo-org.1560.n6.nabble.com/Field-Calculator-calculates-negative-area-tp5042754p5042773.html Sent from the Quantum GIS - User mailing list archive at Nabble.com.